Since the 1990s, global market concentration (the share of global industry sales earned by the largest firms) has increased in the crop seed/biotechnology, agricultural chemical, animal health, animal breeding, and farm machinery industries – all of which invest heavily in agricultural research. By 2009, the largest four firms in each of these industries accounted for at least 50 percent of global market sales. Market concentration was particularly high in animal genetics and breeding, where the four-firm concentration ratio reached 56 percent in 2006/07 (the latest year for which data are available). Growth in global market concentration over 1994-2009 was most rapid in the crop seed industry, where the market share of the four largest firms more than doubled from 21 to 54 percent. This chart is based on data from a table appearing in the December 2012 issue of Amber Waves magazine.